Question

Why does resistance of a metallic conductor increases with increase in temperature class 10

Answer 1

when temperature increases the velocity of free electrons increases bit it also cause increase in amplitude of of vibrationof metalic atoms which cause some extra hindrance or resistance in the path of free electrons.

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Answer 2

$\bf Hey\:There\:!$

The resistance of a conductor increases with an increase in temperature because the thermal velocity of the free electrons increase as the temperature increases. This results in an increase in the number of collisions between the free electrons.